Aerobic Training Enhances Cognition in Vascular Cognitive Impairment

Six months of aerobic training was associated with improved cognitive performance among individuals diagnosed with vascular cognitive impairment.

Sub-cortical ischemic vascular cognitive impairment (SIVCI) is the most common type of VCI and leads to an increased risk of dementia. Previous findings suggest that aerobic exercise may slow SIVCI progression by improving risk factors pertaining to cardiovascular and metabolic functioning, and observational research has found a link between exercise and reduced SIVCI risk.1-3

A randomized controlled trial published in Neurology is the first to investigate the effects of aerobic training on cognitive function in patients with mild SIVCI.4

Researchers at the University of British Columbia in Vancouver, Canada, assigned participants into 1 of 2 groups: One group (n=35) participated in a 6-month program of aerobic training performed 3 times per week, while the other group (n=35) received standard treatment plus education about VCI and healthy nutrition. Follow-up assessments were performed 6 months after the formal aerobic training ended. The main outcomes were cognitive function as evaluated by the Alzheimer's Disease Assessment Scale–Cognitive subscale (ADAS-Cog), executive functions per the Executive Interview (EXIT-25), and activities of daily living as assessed by the Alzheimer's Disease Cooperative Study–Activities of Daily Living (ADCS-ADL).

At the end of the 6-month study period, the ADAS-Cog performance of the exercise group had improved significantly compared to the standard care group (-1.71 point difference, 95% confidence interval [CI], -3.15 to -0.26, P =.02). At the time of the 6-month follow-up assessment, however, the difference was no longer significant (-0.63 point difference, 95% CI, -2.34 to 1.07, P =.46), suggesting that future studies should explore ways to increase ongoing exercise adherence among participants. No significant differences in EXIT-2 or ADCS-ADL scores were observed between groups at either time point.

These findings align with and expand upon previous research demonstrating the cognitive benefits of aerobic exercise in healthy older adults. Such effects could be due to the induction of neurotrophic factor cascades, as has been observed in animal studies, though this relationship in humans is unclear.

“… from a broader physical health perspective, it is well established that aerobic exercise reduces cardiovascular and cardiometabolic risk factors associated with the development and progression of SIVCI,” explained co-author Teresa Liu-Ambrose, PhD, PT, an associate physical therapy professor and director of the Aging, Mobility, and Cognitive Neuroscience Laboratory at the University of British Columbia.

“Of note, in the current study we found that 6 months of aerobic training reduced diastolic blood pressure, and this was associated with improved performance on the ADAS-Cog,” she told Neurology Advisor. The between-group difference in diastolic blood pressure was -6.89 mm Hg (95% CI, -12.52 to -1.26, P =.02). In addition, the aerobic group had better scores on another secondary outcome measure, the 6-minute walk test (30.35 meter difference, 95% CI, 5.82-54.86, P =.02).

Dr Ambrose believes that future research should focus on whether and how different types of exercise might enhance cognitive and brain health in older adults with a risk of dementia. “The more we understand about the ‘what' and ‘how,' the more precise we can be in exercise recommendations for promoting brain health,” she said.

“Given the well-established multidimensional benefits of exercise, as well as the fact that few treatments are available for VCI, exercise appears to be a sensible recommendation with minimal side effects and cost,” she concluded.